psychologywikiaorg-20200213-history
Urinalysis
s seen under a microscope from a urine sample.]] A urinalysis (or "UA") is an array of tests performed on urine and one of the most common methods of medical diagnosis. A part of a urinalysis can be performed by using urine dipsticks, in which the test results can be read as color changes. Medical urinalysis A typical medical urinalysis usually includes: *a description of color and appearance. *specific gravity - normally 1.003 to 1.030. This test detects ion concentration of the urine. Small amounts of protein or ketoacidosis tend to elevate results of the specific gravity. Specific gravity is an expression of the weight of a substance relative to the weight of an equal volume of water. Water has a specific gravity of one. The specific gravity of your urine is measured by using a urinometer. Knowing the specific gravity of your urine is very important because the number indicates whether you are hydrated or dehydrated. If the specific gravity of your urine is under 1.007, you are hydrated. If your urine is above 1.010, you are dehydrated. *pH - normally 5 to 7. *ketone bodies - normally negative (absent). When there is carbohydrate deprivation, such as starvation or high protein diets, the body relies increasingly on the metabolism of fats for energy. This pattern is also seen in people with the disease diabetes mellitus, when a lack of the hormone insulin prevents the body cells from utilizing the large amounts of glucose available in the blood. This happens because insulin is necessary for the transport of glucose from the blood into the body cells. The metabolism of fat proceeds in a series of steps. First, triglycerides are hydrolyzed to fatty acids and glycerol. Second the fatty acids are hydrolyzed into smaller intermediate compounds (acetoacetic acid, betahydroxybutyric acid, and acetone). Thirdly, the intermediate products are utilized in aerobic cellular respiration. When the production of the intermediate products of fatty acid metabolism (collectively known as ketone bodies) exceeds the ability of the body to metabolize these compounds they accumulate in the blood and some end up in the urine (ketonuria). *proteins - normally negative (absent) *Albustix Test - Since proteins are very large molecules (macromolecules), they are not normally present in measurable amounts in the glomerular filtrate or in the urine. The detection of proteins in your urine may indicate that the permeability of the glomerulus is abnormally increased. This may be caused by renal infections or it may be caused by other diseases that have secondarily affected the kidneys such as diabetes mellitus, jaundice, or hyperthyroidism. *nitrites *urobilinogen *Bilirubin - The fixed phagocytic cells of the spleen and bone marrow destroy old red blood cells and convert the heme groups of hemoglobin to the pigment bilirubin. The bilirubin is secreted into the blood and carried to the liver where it is bonded to (conjugated with) glucuronic acid, a derivative of glucose. Some of the conjugated bilirubin is secreted into the blood and the rest is excreted in the bile as bile pigment that passes into the small intestine. The blood normally contains a small amount of free and conjugated bilirubin. An abnormally high level of blood bilirubin may result from: an increased rate of red blood cell destruction, liver damage, as in hepatitis and cirrhosis, and obstruction of the common bile duct as with gallstones. An increase in blood bilirubin results in jaundice, a condition characterized by a brownish yellow pigmentation of the skin and of the sclera of the eye. *Icotest - The test used to detect the destruction of old Red Blood Cells (RBC) in the urine. *glucose - normally negative (absent) *Benedict's Test - Although glucose is easily filtered in the glomerulus, it is not present in the urine because all of the glucose that is filtered is normally reabsorbed from the renal tubules back into the blood. *Hemoglobin Test - Hemolysis in the blood vessels, a rupture in the capillaries of the glomerulus, or hemorrhage in the urinary system may cause hemoglobin to appear in your urine. *RBC number *WBC number *hCG - normally absent, this hormone appears in the urine of pregnant women. Home pregnancy tests commonly detect this substance. Microscopic examination . The urine is under the cover slide, in the upper segment formed by the H-shaped grooves.]] The numbers and types of cells and/or material such as urinary casts can yield a great detail of information and may suggest a specific diagnosis. *Hematuria - associated with kidney stones, infections, tumors and other conditions *Pyuria - associated with urinary infections *eosinophiluria - associated with allergic interstitial nephritis, atheroembolic disease *Red blood cell casts - associated with glomerulonephritis, vasculitis, malignant hypertension *White blood cell casts - associated with acute interstitial nephritis, exudative glomerulonephritis, severe pyelonephritis *(heme) granular casts - associated with acute tubular necrosis *crystalluria -- associated with acute urate nephropathy (or "Acute uric acid nephropathy", AUAN) *calcium oxalatin - associated with ethylene glycol toxicity See also *Uroscopy, the ancient form of this analysis *Medical technologist *Proteinuria References External links *Lab Tests Online: Urinalysis Category:Urine Category:Urine tests